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Category Archives: Processes

This is one of my favourite topics, since I had a large number of systems piping failures related to stress, mostly external.

One of the flange connections of the fire main systems on board a ship, couple of bolts used to break at the head frequently; more often if the ship had done some high-speed manoeuvres. Initially, we used to change the bolt and live with it, but a nagging doubt came into our minds and we did a root cause analysis. What we finally found was that, the last pipe that fitted into the system was a little oversized and had been forced into its slot using a chain pulley, thus leading to a stressed piping section. Whenever high vibrations occurred, the stress used to increase, thus resulting in the flange securing bolts at one end shearing.

I came across a nice article on the topic. Please read and be enlightened on the topic.

I keep getting updates on new products used in the maintenance field through various online subscriptions.

Here is a link that shows the us of Ultrasound devices in the condition based maintenance strategy. I am not trying to sell the product, but am just trying to propagate the techniques involved. Please connect to the link given below and learn more.

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I have seen people getting jittery when confronted with the term Reliability Centred Maintenance or RCM. The management jargon related to RCM makes it virtually difficult for the layman to understand the concept to its practical applications.

While operating gas turbine propelled ships in the Indian Navy, we had a few simple methods to listen to running machinery through rudimentary mechanical stethoscope – a long thin rigid copper tube with a brass disc attached. This was in addition to the more sophisticated on-line vibration measurement equipment, recording the vibration signature continuously. This data used to be periodically analysed to get the vibration signature. At that time, the recording was being done on board, but the data analysis was done by specialists sitting in their labs and we used to get reports on the health of the equipment on a monthly basis.

In one of my earlier posts, I had mentioned a “Look, Listen, Feel” strategy which could be the basic condition monitoring technique. I strongly feel that If Looking, Listening and Feeling are made integral parts of regular visits to the equipment, it forms a practical method in improving reliability of equipment and systems.

Another management jargon that has caught on is “Autonomous Management”. This talks of the equipment and system operators joining hands with the maintenance personnel and getting cross trained with each other’s functions. The operators will be made responsible for the first line maintenance of the equipment or systems that they are in charge of and the maintainers will be trained in basic operations of the same equipment or system. This has the following advantages:

Improved feeling of ownership among both groups – operators and maintainers

Both the groups understand the equipment or system operations and the nuances of reliable operations

Flexibility in operations and maintenance – Who to do what, when, where?